Clinical restenosis after coronary stenting: perspectives from multicenter clinical trials

OBJECTIVES: We sought to evaluate clinical restenosis in a large population of patients who had undergone coronary stent placement. BACKGROUND: One-year success after coronary stenting is limited mainly by restenosis of and requirement for repeat revascularization of the treated lesion.We studied 6,186 patients (6,219 lesions) pooled from several recently completed coronary stent trials. Clinical restenosis was defined using three different definitions: target lesion revascularization (TLR) beyond 30 days, target vessel revascularization (TVR) beyond 30 days, and target vessel failure (TVF), defined as TVR, any death, or myocardial infarction (MI) of the target vessel territory after hospital discharge. RESULTS: By one year, 638 (12.2%) patients had TLR, 748 (14.3%) had TVR, and 848 (16.0%) had TVF, more than two-thirds higher than the rate of these end points at six months. The severity of angiographic restenosis (> or =50% follow-up diameter stenosis [DS]) in 419 of 1,437 (29%) patients undergoing routine angiographic follow-up correlated directly with the likelihood of TLR (73% vs. 26% for >70% DS compared with <60% DS). Smaller pretreatment minimum lumen diameter (MLD), smaller final MLD, longer stent length, diabetes mellitus, unstable angina, and hypertension were independent predictors of TLR. Prior MI and current smoking were negative predictors. CONCLUSIONS: At one year after stenting, most clinical restenosis reflected TLR, which was predicted by the same variables previously associated with an increased risk of angiographic restenosis. The lower absolute rate of clinical restenosis relative to angiographic restenosis was due to infrequent TLR in lesions with less severe (<60% DS) angiographic renarrowing.     

Direct coronary stenting without predilation

OBJECTIVES

Coronary stenting is the primary therapeutic option for percutaneous treatment of many coronary lesions, after the risk of subacute stent thrombosis and bleeding complications has been reduced by improved antithrombotic regimens and high pressure stent expansion.

BACKGROUND

Direct stent implantation (without predilation) has been considered a promising new technique that may reduce the procedure time, radiation exposure time and cost.

METHODS

After having reviewed all cases of stent implantation from February to June 1998 (n = 585), 185 (32%) of these patients were retrospectively considered candidates for direct stent implantation without predilation, according to prespecified criteria (i.e., absence of severe coronary calcifications and/or tortuosity of the lesion or the segment proximal to the lesion). By operator preference, direct coronary stent implantation was actually attempted in 123 (21%) of the 585 patients (100 men, 60 ± 10 years old) on 123 lesions. The impact of direct stenting in terms of cost, procedure time, radiation exposure time and amount of contrast dye used was assessed by comparing the two groups of patients who underwent single-vessel stenting without (n = 69) and with (n = 46) predilation.

RESULTS

Direct stenting was successful in 118 patients (96%). No acute or subacute complications occurred in these patients. Procedure time, radiation exposure time and cost were significantly lower in the group of patients who had single-vessel direct versus conventional stenting (45 ± 31 vs. 64 ± 46 min, 12 ± 9 vs. 16 ± 10 min and 1,305 ± 363 vs. 2,210 ± 803 Euro, respectively; p < 0.05 for all).

CONCLUSIONS

Direct stenting without predilation in selected lesions seems to be a safe and successful procedure that provides a way to contain cost and to shorten radiation exposure time.     

Mechanical debulking versus balloon angioplasty for the treatment of true bifurcation lesions

Objectives. The purpose of this study was to compare the immediate angiographic and long-term results of debulking versus balloon angioplasty for treatment of true bifurcation lesions.

Background. Previous studies have shown true bifurcation lesions to be a high risk morphological subset for percutaneous transluminal coronary angioplasty (PTCA). Although atherectomy devices have been used to treat bifurcation lesions, no studies have compared the outcomes of these alternative treatment modalities.

Methods. Between January 1992 and May 1997, we treated 70 consecutive patients with true bifurcation lesions (defined as a greater than 50% stenosis in both the parent vessel and contiguous side branch) with conventional PTCA (n = 30) or debulking (with rotational or directional atherectomy) plus adjunctive PTCA (n = 40). Paired angiograms were analyzed by quantitative angiography, and clinical follow-up was obtained in all patients.

Results. Acute procedural success was 73% in the PTCA group and 97% in the debulking group (p = 0.01). Major in-hospital complications occurred in two patients in the PTCA group and one in the debulking group. Treatment with atherectomy plus PTCA resulted in lower postprocedure residual stenoses than PTCA alone (16 ± 15% vs. 33 ± 17% in the parent vessel, and 6 ± 15% vs. 39 ± 22% in the side branch; p < 0.001 for both comparisons). At 1 year follow-up, the incidence of target vessel revascularization (TVR) was 53% in the PTCA group as compared with 28% in the debulking group (p = 0.05). Independent predictors of the need for repeat TVR were side branch diameter >2.3 mm, longer lesion lengths, and treatment with PTCA alone.

Conclusions. For the treatment of true bifurcation lesions, atherectomy with adjunctive PTCA is safe, improves acute angiographic results, and decreases target vessel revascularization compared to PTCA alone. The benefits of debulking for bifurcation lesions were especially seen in lesions involving large side branches.     

Quantitative angiographic methods for appropriate end-point analysis, edge-effect evaluation, and prediction of recurrent restenosis after coronary brachytherapy with gamma irradiation.

OBJECTIVES: The study was done to investigate the relationship between clinical restenosis and the relative angiographic location of the recurrent restenotic lesion, after treatment of in-stent restenosis with vascular brachytherapy in the Washington Radiation for In-Stent Restenosis Trial (WRIST). BACKGROUND: Intracoronary radiation therapy reduces recurrence of in-stent restenosis. We investigated the above objective in patients enrolled in WRIST. METHODS: The WRIST study randomized 130 patients to double-blinded therapy with gamma irradiation (iridium-192 [(192)Ir]) versus placebo after interventional treatment of diffuse in-stent restenosis. After the intervention and at follow-up, three vessel segments were individually analyzed with quantitative coronary angiography: 1) the "stent," 2) the "radiation ribbon," and 3) the "ribbon+margin" segment (including 5 mm on either end of the injured or radiation-ribbon segment). Receiver operator curves (ROC) were used to assess the value of the follow-up percent diameter stenosis (DS) for each of the three analyzed segments in predicting target vessel revascularization (TVR). RESULTS: (192)Ir reduced recurrent restenosis (23.7% vs. 60.7%, p < 0.001) and the length of recurrent restenosis (8.99 +/- 4.34 mm vs. 17.54 +/- 10.48 mm, p < 0.001) at follow-up compared to placebo. Isolated stent edge (3.4%) and ribbon edge (1.7%) restenoses were infrequent in both groups. The best angiographic surrogate of TVR was the 50% follow-up DS obtained from the ribbon+margin analysis (ROC area 0.806). CONCLUSIONS: In WRIST, not only was (192)Ir therapy effective in reducing restenosis, but it also reduced the lesion length of treatment failures by 50%, and it was not associated with edge proliferation. The restenosis rate obtained from the vessel segment inclusive of the dose fall-off zones was the best correlate of TVR and should become a standard analysis site in all vascular brachytherapy trials.     

Referral for coronary artery revascularization procedures after diagnostic coronary angiography: Evidence for gender bias?

Objectives. We sought to determine whether there is a gender bias in the selection of patients for coronary revascularization once the severity of the underlying coronary artery disease has been established with angiography.

Background. It has been suggested that women with coronary artery disease are less likely to be referred for coronary angiography and coronary artery bypass surgery than men. Whether such a referral bias for revascularization procedures, including coronary angioplasty, is present once angiography has been performed is not clear.

Methods. We retrospectively analyzed 22,795 patients with suspected coronary artery disease who underwent coronary angiography between 1981 and 1991 and compared the numbers of women and men who underwent either coronary artery bypass surgery or coronary angioplasty within 30 days of coronary angiography.

Results. Angiography revealed significant (one-vessel or more) disease in 15,455 patients (52% of women, 76% of men). Despite worse symptoms, women had less extensive coronary disease than men as judged by the number of vessels diseased. Women were also more likely to have other co-morbid diseases. An equal proportion of women (54%) and men underwent revascularization procedures. After adjustment for baseline differences and age, differences in the two individual revascularization strategies were very small: More women tended to have coronary angioplasty ([absolute difference ± 1 SD] + 3.3 ± 0.7%, p < 0.0001), but fewer had coronary artery bypass surgery than men (−2.5 ± 0.8%, p = 0.003). When the two revascularization strategies were considered together, there was no significant gender difference in overall adjusted use of revascularization (+0.8 ± 0.9%, p = 0.41).

Conclusions. Once diagnostic coronary angiography had been performed, no major differences in the overall utilization of revascularization procedures were noted for women compared with men.     

Two-year outcome of patients treated with sirolimus- versus paclitaxel-eluting stents in an unselected population with coronary artery disease (from the REWARDS Registry)

Multiple studies comparing sirolimus-eluting stents (SES) and paclitaxel-eluting stents (PES) in patients with coronary artery disease have been performed. Despite these comparisons, it remains uncertain whether a differential in long-term efficacy and safety exists. Unselected patients treated exclusively with 1 drug-eluting stent type were enrolled in the Registry Experience at the Washington Hospital Center with Drug-Eluting Stents. There were 2,099 patients (3,766 lesions) treated with SES and 1,079 patients (1,850 lesions) treated with PES. Patients were followed at 30 days, 1 year, and 2 years for the clinical endpoints of death, myocardial infarction, target vessel revascularization, and definite and definite/probable stent thrombosis. Patients in the SES group had more dyslipidemia, history of congestive heart failure, and ostial lesions; patients treated with PES had more previous coronary artery bypass surgery, unstable angina, and type C lesions. At 2 years, unadjusted major adverse cardiac events (MACE) (22.6% vs 21.1%, p = 0.3) and target vessel revascularization (13.3% vs 11.2%, p = 0.1) were comparable. The incidence of definite stent thrombosis was higher in the SES group (1.8% vs 0.9%, p = 0.05) driven by early events. Similar results were seen after adjustment for baseline differences: MACE (hazard ratio 1.1, 95% confidence interval [CI] 0.9 to 1.3, p = 0.5), definite stent thrombosis (hazard ratio 2.3, 95% CI 1.0 to 5.2, p = 0.05), and target vessel revascularization (hazard ratio 1.1, 95% CI 0.9 to 1.4, p = 0.4). The incidence and rate of late stent thrombosis (>30 days) were similar (0.7% vs 0.5%, p = 0.4 and 0.24%/year, both groups, respectively). In conclusion, no major differential in long-term safety or efficacy was detected between SES and PES; both stent types were efficacious in reducing revascularization but were limited by a small continual increase in late stent thrombosis.     

Clinical and angiographical results of the use of the EPHESOS stent in patients with coronary artery atherosclerosis

The Ephesos is a new balloon-expandable, stainless steel, tubular stent with multicellular design. This open nonrandomized study assesses the immediate and long-term clinical and angiographic outcomes after Ephesos implantation in patients with native coronary artery disease. The Ephesos was implanted in 168 patients with 198 de novo lesions. Most patients (56%) had unstable angina, and 38% of lesions were type B2-C. The mean lesion length was 12.5-/+7.2 mm, and 29% of lesions were >15 mm in length. No stent deployment failure occurred, as well as acute or subacute stent thrombosis. In-hospital non-Q-wave myocardial infarction occurred in 2 patients. The 6-month event-free survival was 83.9%. Two patients with no restenosis in the target vessel died of fatal infarction due to abrupt closure of a nontarget vessel. The 6-month angiographic follow-up was obtained in 164 patients (98%) (192 lesions). The loss index was 0.27-/+0.25. Angiographic restenosis rate was 12%. Twenty patients with restenosis had repeat target lesion revascularization. The results of this study indicate a potential benefit of EPHESOS for the prevention of stent thrombosis and restenosis in these relatively high-risk patients.     

Impact of vessel size, lesion length and diabetes mellitus on angiographic restenosis outcomes: insights from the NIRTOP study

BACKGROUND: The primary objective of the current analysis was to define the impact of vessel size, lesion length, and diabetes on clinical and angiographic restenosis following implantation of the NIRFLEX stent. METHODS AND RESULTS: Clinical and angiographic restenosis outcomes and multivariate predictors were compared between patients treated in 'small' (<3 mm, n=113 pts/133 lesions) versus 'large' (> or =3 mm, n=41 pts/53 lesions) vessels; between 'tubular' (10-20 mm lesion length n=49 pts/51 lesions) versus 'discrete' (<10 mm lesion length n=103 pts/133 lesions) lesions; and between 'diabetic' (n=30/35 lesions) versus 'non-diabetic' (n=128/156 lesions) patients using the flexible closed-cell design 'bare-metal' NIRFLEX stent in patients with native coronary artery disease. At six month follow-up, target vessel revascularization (TVR) and target lesion revascularization (TLR) rates were significantly less frequent in the 'large' versus 'small' vessel group (2.4% versus 16.8% for TVR, P=0.016, 0% versus 12.4% for TLR, P=0.022). Likewise, angiographic late loss was lower in 'large' versus 'small' vessels (0.54 versus 0.70 mm, P=0.05). Lesion length affected MACE rates but not angiographic restenosis. Angiographic late loss was greater in diabetics compared to the non-diabetic group (0.89 versus 0.60 mm, P=0.003). Using a multivariate model, diabetes mellitus (odds ratio=2.65, P=0.047) and post-procedure in-stent MLD (mm) (odds ratio=0.178, P=0.0019) were major determinants of restenosis. CONCLUSION: Clinical and angiographic restenosis outcomes following NIRFLEX stent implantation were dependent upon vessel size, lesions length, post-procedural stent lumen dimensions, and the diabetic status.     

Chlamydia pneumoniae in the atherosclerotic plaques of patients with unstable angina undergoing coronary artery bypass grafting: does it have prognostic implications?

Objective: This study sought to evaluate the prognostic significance of the presence of DNA of Chlamydia pneumoniae in the coronary atherosclerotic lesions of patients with unstable angina. Background: C. pneumoniae has been implicated in the pathogenesis of coronary artery disease by serological and pathological studies, but whether antichlamydial antibodies and the presence of this pathogen in the coronary atherosclerotic tissue are related to prognosis in unstable angina remains unclear. Methods: A total 76 coronary specimens from 45 patients with unstable angina undergoing bypass surgery were subjected to nested polymerase chain reaction (PCR) for C. pneumoniae. Antichlamydial immunoglobulin G (IgG), A (IgA) and M (IgM) were also examined by an enzyme immunoassay. Patients were followed during a 2-year period to determine the incidence of adverse cardiovascular events. Results: DNA of C. pneumoniae was detected in 57 (75%) of 76 atherosclerotic lesions: 39 patients showed a positive PCR result in at least one plaque. Of the 45 patients, 44 (97.7%) showed a positive serological result: IgG was positive in 39 (86.6%) patients, IgM in five (11.1%) patients and IgA in 42 (93.3%). Clinical characteristics and serologic results were similarly distributed in patients with and without infected lesions at enrollment. At least one adverse event occurred in 21 (46.6%) of the 45 patients at 2 years: death in nine (20%), recurrent angina in 12 (26.6%), revascularization in six (13.3%) and myocardial infarction in two (4.4%) patients. The composite endpoint of death, myocardial infarction, recurrent angina and revascularization at 2-year follow-up did not differ according to the PCR or serologic results. Conclusions: The presence of C. pneumoniae in coronary atherosclerotic plaques of patients with unstable angina undergoing coronary bypass grafting does not have prognostic significance. In addition, serology does not allow us to differentiate those patients with plaque infection by C. pneumoniae and also does not provide any prognostic information in these patients.     

Treatment of coronary bifurcation lesions by stent implantation only in parent vessel and angioplasty in sidebranch: immediate and long-term outcome

The aim of this study was to evaluate the immediate and long-term outcome of intracoronary stent implantation for the treatment of bifurcation lesions. We treated 30 patients with bifurcation stenosis with the Bx Velocity stent implanted only in the parent vessel and with balloon angioplasty of the sidebranch. Angiographic success was 86.7% (n = 26 patients) in both branches and 100% in the main branch. Clinical success was achieved in 29 patients (96.7%). One patient (3.3%) suffered from a small non-Q wave myocardial infarction. All 30 patients underwent control coronary angiography at 6 months unless performed earlier due to symptoms. After the 6-month follow-up, a total of 27 patients (90%) were asymptomatic; angiographic restenosis (> 50%) was found in four cases (13.3%). There was no sidebranch restenosis. During the follow-up, one patient (3.3%) had unstable angina and angiography revealed severe diffuse restenosis within the whole stent; this patient was referred for coronary artery bypass surgery. Two patients had mild angina (Canadian Cardiovascular Society Class II) and 1 patient had silent ischemia during exercise stress test. These patients underwent repeat coronary angioplasty. The rate of major adverse cardiac events was 16.6% and target vessel revascularization rate was 13.3%. We concluded that stent implantation only in the parent vessel with angioplasty of the sidebranch in bifurcation lesions is safe and has a high clinical success rate and low rate of target lesion revascularization.     

Adjunctive stent implantation following directional coronary atherectomy in patients with coronary artery disease

Objectives. This prospective case-control study evaluated the acute and long-term results of stent implantation preceded by debulking of the plaque by means of directional coronary atherectomy.

Background. In comparison with balloon angioplasty, intracoronary stenting produces a larger luminal diameter, maintains artery patency and reduces the incidence of restenosis. Optimal stent deployment is a pivotal factor for achieving the best results, but the bulk of the atherosclerotic plaque opposes stent expansion and may limit the success of the procedure. Debulking of the plaque may provide a better milieu for optimal stent deployment.

Methods. Directional coronary atherectomy followed by a single Palmaz-Schatz stent implantation was attempted in 100 patients. The successes, complications and angiographic results of the combined procedure were evaluated both acutely and during follow-up. Matched patients undergoing successful Palmaz-Schatz stent implantation alone during the same period served as controls.

Results. Atherectomy followed by stent implantation was performed in 94 patients with 98 lesions; periprocedural complications were observed in four cases. The stenosis diameter decreased from 76 ± 9% at baseline to 30 ± 13% after atherectomy (p < 0.0001), and 5 ± 9% after stent implantation (p < 0.0001); it increased to 27 ± 15% at 6-month angiography (p < 0.0001). During the 14 ± 10 months of follow-up, none of the patients died or experienced myocardial infarction, but three patients underwent target lesion revascularization. The patients undergoing stent implantation alone achieved smaller acute gains, tended to have a higher late lumen loss, had a higher restenosis rate (30.5% vs. 6.8%, p < 0.0001) and showed a greater incidence of clinical events during follow-up (p < 0.0001).

Conclusions. Debulking atherosclerotic lesions by means of directional coronary atherectomy before stent implantation is a safe procedure with a high success rate and a low incidence of restenosis at follow-up.     

Hemodynamic effects of sildenafil in patients with stable ischemic heart disease

Background: Recently the new specific phosphodiesterase-5 inhibitor sildenafil was introduced into therapy for erectile dysfunction. The hemodynamic effects of sildenafil may be potentially hazardous for patients with cardiac disease. Sildenafil has been reported to augment the hypotensive effects of nitrates. There is sparse information regarding the systemic and pulmonary hemodynamic effects of a single oral dose of sildenafil in patients with stable angina. Methods: Male patients referred for coronary angiography with diagnosis of chronic stable angina were enrolled in this study to assess the acute hemodynamic effects of sildenafil. Patients receiving long-acting or sublingual nitrates for the last 6 h before the study were excluded. Hemodynamic measurement were taken during right and left heart catheterization in the basal state and 60 min after 50 mg of oral sildenafil. Results: Twelve patients (age 53±7 years) were studied. All had stable angina CCS class II or III. Four had previous myocardial infarction. By coronary angiography, seven patients had at least one coronary artery with >70% stenosis, four had at least one with 50–70% stenosis, and one had only intimal irregularities. There were no significant effects of sildenafil on systemic or pulmonary arterial pressure, left ventricle endiastolic pressure, cardiac output, and systemic or pulmonary vascular resistance (P>0.05 for all). No adverse events were observed. Conclusion: A single oral dose of sildenafil had no significant hemodynamic effect in supine patients with stable angina. Isolated administration of sildenafil does not appear to be associated to adverse cardiovascular effects.     

Sirolimus-eluting stents for the treatment of atherosclerotic ostial lesions

BACKGROUND: Ostial atherosclerotic lesions are distinct from other lesion sites in terms of outcomes following percutaneous interventions. Despite aggressive lesion modification strategies, long-term outcome is hampered by restenosis. Various stent designs have failed to show significant improvement in target lesion revascularization (TLR) rates. The present study evaluates the clinical outcomes following sirolimus-eluting stent implantation for ostial lesions. MATERIALS AND METHODS: The sirolimus-eluting stent (SES) was the device of choice at our institute for all coronary interventions from April 2002 to March 2003. This study population is comprised of 50 patients who received drug-eluting stents for atherosclerotic ostial lesions during this period. Sixty-eight percent of the patients were male and 24 patients (48%) had a history of previous revascularization. Indication for intervention were as follows: acute myocardial infarction, 7 patients (14%), stable angina, 23 patients (46%), unstable angina, 20 patients (40%). Angioplasty and stent implantations were done according to the standard protocol. All patients were prospectively followed up for major adverse cardiac events. The event-free survival was 90% at one year. There were 5 (10%) target vessel revascularization, 3 (6%) myocardial infarctions and 1 (2%) death during a mean follow-up of 414.5 +/- 54.5 days. TLR was required in 4 (8%) patients. CONCLUSIONS: SES implantation is feasible in ostial locations and is associated with low subsequent revascularization.     

Angiographic and clinical outcome of a new self-expanding intracoronary stent (RADIUS): results from multicenter experience in Japan.

The RADIUS coronary stent featuring a multisegmented slotted tube design and self-expanding nitinol delivery system has a high radial force and flexibility, uniform expansion, and contours to the shape of the vessel. Successful stent deployment was achieved in 104 stable angina patients (106 lesions; 44% LAD, 19% circumflex, and 37% RCA). Mean minimal lumen diameter (MLD) increased from 0.77 +/- 0.46 mm to 2.88 +/- 0.61 mm and mean percent diameter stenosis (% DS) decreased from 73 +/- 14% to 6 +/- 13% immediately after the procedure. At 6-month follow-up, two patients (2%) underwent urgent target revascularization, and cerebral bleeding occurred in one patient (1%). Angiographic follow-up was performed in 94 lesions (89%) and mean MLD and mean % DS were 2.08 +/- 0.92 mm and 30% +/- 24%, respectively. Stent restenosis (>50% diameter stenosis at follow-up) was observed in 16 (17%) of all lesions. The high success rate for stent deployment, low incidence of major adverse cardiac event, and lower restenosis rate after stent implantation indicate that the RADIUS stent is useful for coronary intervention.     

Clinical and angiographic outcome after coronary arterial stenting with the carbostent

The Carbostent is a new balloon-expandable, stainless steel, tubular stent with innovative multicellular design and unique turbastratic carbon coating (Carbofilm). This open nonrandomized 2-center study assesses the immediate and long-term clinical and angiographic outcomes after Carbostent implantation in patients with native coronary artery disease. The Carbostent was implanted in 112 patients with 132 de novo lesions. Most patients (55%) had unstable angina, and 38% of lesions were type B2-C. The mean lesion length was 12.5 +/- 7.0 mm, and 29% of lesions were > 15 mm in length. No stent deployment failure occurred, as well as acute or sub-acute stent thrombosis. The 6-month event-free survival was 84 +/- 4%. One patient with a stented right coronary artery and no restenosis at the angiographic follow-up died after 6 months of fatal infarction due to abrupt closure of a nontarget vessel. In-hospital non-Q-wave myocardial infarction occurred in 1 patient, and 11 patients had repeat target lesion revascularization (target lesion revascularization rate 10%). The 6-month angiographic follow-up was obtained in 108 patients (96%) (127 lesions). Angiographic restenosis rate was 11%. The loss index was 0.29 +/- 0.28. The results of this study indicate a potential benefit of Carbostent for the prevention of stent thrombosis and restenosis in these relatively high-risk patients. A larger trial is being planned to confirm these promising results.     

Predictors of outcome after sirolimus-eluting stent implantation for complex in-stent restenosis

Few data are available on the effectiveness of sirolimus-eluting stent implantation for the treatment of in-stent restenosis, and no data exist about the predictors of outcome after sirolimus-eluting stent implantation for complex in-stent restenosis (diffuse, proliferative, or total occlusion). From April 2002 to May 2004, 136 patients with 161 complex in-stent restenoses underwent sirolimus-eluting stent implantation. At 9 months, 5 patients had died (3 of cardiac and 2 of noncardiac causes), no reinfarctions had occurred, and 11 target vessel revascularization procedures had been performed. The target vessel revascularization rate was 8%, and the in-segment binary restenosis rate was 17%. The predictors of the risk of recurrence were unstable angina as the clinical presentation of in-stent restenosis, an ostial location of the target lesion, lesion length, and sirolimus-eluting stent diameter < or =2.5 mm.     

Acute and long-term results of bifurcation stenting (from the Coroflex Registry)

Angioplasty of bifurcation lesions represents a continuing challenge. A total of 421 consecutive patients were prospectively followed in a registry on bifurcation stenting with a high-end bare metal stent (Coroflex, BBraun, Berlin, Germany), allowing side branch percutaneous transluminal coronary angioplasty through the stent struts without distraction of the main vessel stent from the vessel wall or other distortions. This approach obviated the 2-wire technique and kissing balloons. Detailed data, including lesion location, stenosis morphology, procedural success, and hospital and follow-up major adverse cardiac events (MACEs; acute myocardial infarction, death, revascularization, hospitalization due to angina), were collected from 6 European centers. Of the patients, 60% had stable angina, 23% had unstable angina pectoris/non-ST-elevation myocardial infarction, and 17% had ST-elevation myocardial infarction. In 17% of patients, the main vessel alone was stented; in 71%, stenting of the main vessel was complemented by side branch percutaneous transluminal coronary angioplasty. Technical success (residual stenosis <50%) in the 2 branches was achieved in 90% (main vessel in 99%). The rate of MACEs at discharge was 2%. After 6 months, 17% of patients had undergone target lesion revascularization or coronary artery bypass grafting. The total 6-month MACE rate was 22%. In conclusion, successful bifurcation stenting with a low MACE rate is possible in most patients using a simplified approach with a dedicated high-end bare metal stent.     

雷帕霉素涂层支架治疗老年人冠心病的疗效及再狭窄的随访分析

目的 观察雷帕霉素涂层冠状动脉Cypher支架治疗老年冠心病患者的临床疗效及再狭窄情况。方法 2002年11月至2005年5月在我院心导管室接受Cypher支架治疗的328例60岁以上的老年冠心病患者，观察术后即刻效果，随访6个月记录心脏性死亡、心肌梗死、再次血管重建事件，并进行冠状动脉造影复查。328例中，ST段抬高的急性心肌梗死66例，非ST段抬高的急性心肌梗死21例，不稳定心绞痛149例，稳定型心绞痛92例。结果 支架植入成功率99．1％（325／328），住院期间无死亡。随访6个月出现急性和亚急性血栓各1例，晚期血栓致心肌梗死2例，心力衰竭死亡1例，进行血管重建术7例。住院其间主要心脏不良事件发生率0．6％（2／328），6个月心脏不良事件发生率3．7％（12／328）。术后6个月84例患者冠状动脉造影复查显示，再狭窄率为8．3％（7／84），支架内为2．4％（2／84），靶病变重建率为5．9％（5／84）。结论 应用Cypher支架治疗老年人冠心病是安全和有效的，主要心脏不良事件发生率低，支架内再狭窄率和靶病变重建率明显低于普通金属支架。     

Comparison of Men Versus Women in Cross-Sectional Area Luminal Narrowing, Quantity of Plaque, Presence of Calcium in Plaque, and Lumen Location in Coronary Arteries by Intravascular Ultrasound in Patients with Stable Angina Pectoris

Women have an increased mortality after coronary interventions compared with men, which may be partly explained by differences in comorbid clinical conditions. However, whether women also have quantitative differences in coronary atherosclerosis is not known. Preinterventional intravascular ultrasound (IVUS) was used to study de novo, nonostial native coronary lesions in 169 women and 549 men with chronic angina. The external elastic membrane (EEM), lumen, and plaque + media (P + M) areas, plaque burden, plaque eccentricity, and calcium were measured at the target lesion and at a proximal reference site. All cross-sectional IVUS measures were also corrected for body surface area. Results are reported as mean ± 1 SD. Women had significantly smaller reference site EEM (16.5 ± 5.3 vs 19.4 ± 6.3 mm², p <0.0001), lumen (8.7 ± 3.0 vs 9.9 ± 4.0 mm², p = 0.0020), and P + M areas (7.8 ± 3.7 vs 9.5 ± 4.2 mm², p = 0.0001). Women also had significantly smaller lesion site EEM (16.2 ± 5.9 vs 18.3 ± 6.7 mm², p = 0.0028), lumen (2.4 ± 1.7 vs 2.9 ± 2.6 mm², p = 0.0273), and P + M areas (13.6 ± 5.7 vs 15.3 ± 6.4 mm², p = 0.0112). However, when corrected for BSA, these differences were no longer significant. Women and men also had similar reference and lesion plaque burden, eccentricity, and calcium. Preinterventional IVUS analysis failed to detect any quantitative or qualitative differences in coronary atherosclerosis in men compared with women.

To determine whether there are quantitative differences in coronary atherosclerosis in men compared with women, preinterventional intravascular ultrasound (IVUS) was used to study de novo, nonostial native vessel lesions in 169 women and 549 men with chronic angina. Women had significantly smaller reference segment and target lesion external elastic membrane, lumen, and plaque cross-sectional areas; however, when corrected for body surface area, these differences were no longer significant. Women and men also had similar reference segment and target lesion plaque burden, eccentricity, and calcification. Preinterventional IVUS analysis failed to detect any quantitative differences in coronary atherosclerosis in men compared with women.     

Stenting small coronary arteries: The Multi-Link PIXEL Multicenter Italian Registry

BACKGROUND: Published data regarding stenting small coronary arteries are still limited and controversial. The Multi-Link Pixel stent is a new, corrugated ring, stainless-steel stent specifically designed for small vessels. The feasibility, safety and efficacy of implantation of the Pixel coronary stent in vessels with reference diameter 2.5 mm were prospectively studied with a multicenter Italian registry. METHODS AND RESULTS: A total of 231 patients (243 lesions) were included in the study. The risk profile of the study population was high (41% of cases were treated for unstable angina, 20% had diabetes and 52% had multivessel disease). Forty percent of lesions had unfavorable characteristics (type B2 or C) and 10% were chronic total occlusions. Successful stent deployment was achieved in all lesions. Minimal lumen diameter significantly increased from 0.71 0.32 mm to 2.32 0.40 mm and diameter stenosis decreased from 67.20 12.49% to 6.68 10.68%. The acute lumen gain was 1.58 0.25 mm. There were no major in-hospital complications and no cases of acute or subacute stent thrombosis. The rate of major adverse cardiac events was 0.4% at 14 days and 9.6% at 6 months. Target lesion revascularization was 0.4% at 14 days and 7.4% at 6 months. Most patients improved in their clinical symptoms. CONCLUSION: This initial experience indicates that implantation of the Multi-Link Pixel stent appears to be safe and effective in the treatment of complex coronary lesions in small vessels and is associated with a remarkably low target vessel revascularization rate.